Table of Contents
What is the objective of this page?
Info |
---|
To help users to improve S2S CMA MARS requests performance via the WebAPI.
|
How is the S2S reforecast data organised in MARS?
Info |
---|
In general it is organised, as a huge tree, with the indentation below, showing different levels down that tree:
|
What would be the natural way to group requests?
Info |
---|
The idea is to request as much data as possible from the same tape file. The natural way to group requests would be:
|
Best practise to iterate over all hindcastDates of several hindcastYears for CMA
Info |
---|
|
Info |
---|
for hindcastYear in hindcastYears |
Web-API examples:
A CMA reforecast request for all the available hindcastDates
Info |
---|
|
Code Block | ||
---|---|---|
| ||
#!/usr/bin/env python import calendar from ecmwfapi import ECMWFDataServer server = ECMWFDataServer() origin = "babj" modelVersionDate = "2014-05-01" def retrieve_cma_reforecast(): """ A function to demonstrate how to iterate efficiently over all hindcastYears, hindcastMonths etc for a particular cma_reforecast_request. Change the variables below to adapt the iteration to your needs """ hindcastYearStart = 1994 hindcastYearEnd = 2014 hindcastMonthStart = 1 hindcastMonthEnd = 12 for hindcastYear in list(range(hindcastYearStart, hindcastYearEnd + 1)): for hindcastMonth in list(range(hindcastMonthStart, hindcastMonthEnd + 1)): numberOfDays = calendar.monthrange(hindcastYear, hindcastMonth)[1] for hindcastDay in list(range(numberOfDays)): hindcastDate = '%04d%02d%02d' % ( hindcastYear, hindcastMonth, hindcastDay + 1) target = "%s%s.grb" % (origin, hindcastDate) cma_reforecast_request(hindcastDate, target) def cma_reforecast_request(hindcastDate, target): """ A CMA reforecast request. Change the keywords below to adapt it to your needs. """ server.retrieve({ "class": "s2", "dataset": "s2s", "date": modelVersionDate, "expver": "prod", "hdate": hindcastDate, "levtype": "sfc", "origin": origin, "param": "165/166", "step": "24/to/1440/by/24", "stream": "enfh", "target": target, "time": "00", "number": "1/2/3", "type": "pf", }) if __name__ == '__main__': retrieve_cma_reforecast() |
Useful links
Info |
---|